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Full-Text Articles in Condensed Matter Physics
Generally Covariant Theory Of Multipole Moment Conserving Quasiparticles, Gavin Eric Riley
Generally Covariant Theory Of Multipole Moment Conserving Quasiparticles, Gavin Eric Riley
Honors Theses and Capstones
This report represents the creation of a field theory which is capable of describing quasiparticle excitations that preserve 2^k -pole moments. These quasiparticles exhibit certain ’semidynamic’ properties such as individual particle immobility but free movement of bound 2^L-tuples. We provide a review of work done on dipole conserving fractons and their dynamics [1] and expand upon it to describe higher moment conserving systems with global quadratic (and higher) phase symmetry. This requires the selection of the temporal and spatial directions. The selection of a temporal direction is done with a foliation defined by an anisotropic scaling of space and time, …
Attempts To Measure Nanosecond Resolved Electronic Dynamics Of Charge Density Wave Phase Transition In 1t-Tas2, Ben Campbell
Attempts To Measure Nanosecond Resolved Electronic Dynamics Of Charge Density Wave Phase Transition In 1t-Tas2, Ben Campbell
Honors Theses and Capstones
Scanning tunneling microscopes allow for atomic spatial resolution but the resulting images are necessarily time-averaged and fast dynamics are lost. Pump-probe spectroscopy is a common optical technique used to measure ultrafast electronic dynamics but the integration of optical pump-probe spectroscopy into an STM requires specialized knowledge and equipment. Alternatively, an all-electronic pump-probe spectroscopy technique has recently been developed for use with an STM that replaces the laser pulses of optical pump-probe with voltage pulses. In this paper, I implemented an all-electronic pump-probe scheme into an existing scanning tunneling microscope using an arbitrary waveform generator and a lock-in amplifier. I developed …
Thermally Driven Topology And The Topological Hall Effect In Chiral Magnets, Tan Dao
Thermally Driven Topology And The Topological Hall Effect In Chiral Magnets, Tan Dao
Honors Theses and Capstones
No abstract provided.
Investigating The Time Scales Of Electromechanical Motion In Graphene Drumheads Using Pump-Probe Spectroscopy With Stm, Alana P. Gudinas
Investigating The Time Scales Of Electromechanical Motion In Graphene Drumheads Using Pump-Probe Spectroscopy With Stm, Alana P. Gudinas
Honors Theses and Capstones
Scanning tunneling microscopy (STM) has transformed the field of condensed matter physics over the past few decades, allowing scientists to image materials at the atmomic scale, manipulate individual atoms, and probe electronic states on the surface of materials. In recent years, there have been numerous developments to introduce time-resolved measurements to STM in order to probe atomic-scale dynamic processes and combine spatial and temporal resolution. Advances like THz-STM setups achieve femtosecond resolution, but require complex external setups. All-electronic pump-probe spectroscopy for STM (directly analogous to optical pump-probe spectroscopy) has been pioneered by Loth et al., and newer applications (Natterer et …
Sensitivity Of Black Phosphorus To O2 And Atmosphere Measured By Macroscopic Four-Point Probe, Cameron Flynn
Sensitivity Of Black Phosphorus To O2 And Atmosphere Measured By Macroscopic Four-Point Probe, Cameron Flynn
Honors Theses and Capstones
Scientific interest in black phosphorus, a two-dimensional semiconducting allotrope of phosphorus, has increased in the last few years, since it was shown in 2014 to have very good properties for fieldeffect transistors. Unfortunately, practical use of the material is delayed because of its tendency to degrade into a phosphoric oxide when left in air. In this thesis I present the effects of atmospheric air and pure oxygen on the transport properties of bulk black phosphorus with and without light exposure. For continuous measurements carried out by millimeter-scale four-point probe, we see no change in the resistance of bulk samples exposed …